update interface of GraphQLResponse for multitenant (#760)

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### What

Update the interface of `GraphQLResponse`
- make some functions public
- added some helper functions that are used in v3-engine-multitenant
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obvious)? -->

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### How

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V3_GIT_ORIGIN_REV_ID: 691ff8e3505f96ba9e9a2e8518023e4812319a05

v3/crates/execute/src/lib.rs

@@ -65,17 +65,25 @@ impl<'a> TraceableError for GraphQLErrors<'a> {
 pub struct GraphQLResponse(gql::http::Response);
 
 impl GraphQLResponse {
-    fn from_result(result: ExecuteQueryResult) -> Self {
+    pub fn from_result(result: ExecuteQueryResult) -> Self {
         Self(result.to_graphql_response())
     }
 
-    fn from_error(err: &error::RequestError) -> Self {
+    pub fn from_error(err: &error::RequestError) -> Self {
         Self(Response::error(
             err.to_graphql_error(),
             axum::http::HeaderMap::default(),
         ))
     }
 
+    pub fn from_response(response: gql::http::Response) -> Self {
+        Self(response)
+    }
+
+    pub fn does_contain_error(&self) -> bool {
+        self.0.does_contains_error()
+    }
+
     pub fn inner(self) -> gql::http::Response {
         self.0
     }